Advances in embedded controller technology have enabled computer mass storage devices having embedded controllers to include self-contained test, adaptation, upgrade and diagnostics capabilities. For example, modem streaming linear tape drives, such as the present assignee's DLTT.TM. tape drive products are equipped to perform very comprehensive tests, and these drives store a large amount of information about failure modes and applicable commands, and maintain this information even during a power failure. These drives also have an important capability allowing updating of drive control software any time an upgrade is required or desired.
Diagnostic routines have been carried out via communications over the main bus structure interconnecting the storage device with a host computer, such as a Small Computer System Interface (SCSI) bus. While testing over the primary bus is practical so long as the interface remains functional, the primary bus interface structure remains the only direct access to the embedded controller. Some error or diagnostic conditions make use of the primary bus structure impractical. Also, after the drive has been installed in the computer, diagnosis of fault conditions possibly involving the drive has typically required entry into the computer housing, and frequently the removal of the drive for separate testing and handling. As disk drives are being made to store ever-increasing amounts of user data, the drives have become more sensitive to handling during installation and removal. Thus, minimizing handling of hard disk drives after installation into a computer would be very desirable in order to minimize damage.
Present state-of-the-art tape drives and other mass storage devices frequently make use of a variety of port expanders, serial ports and special command sets over the SCSI bus primary interface in order to provide input and output for testing and problem diagnosis during the design, validation and manufacturing processes.
One example of a secondary port useful for data exchange within the design, validation and manufacturing processes is described in U.S. Pat. No. 4,979,055 to Squires et al., entitled: "Disk Drive System Controller Architecture Utilizing Embedded Real-Time Diagnostic Monitor". The Squires et al. patent describes a micro-controller based hard disk drive. A secondary serial port and communications path was provided from the micro-controller to a "dumb" terminal. Results of a diagnostic monitor routine executed by the micro-controller were communicated via the serial port to the dumb terminal and displayed thereon for later analysis and/or corrective action by the design/manufacturing team. In addition, the secondary serial port enabled diagnostic routines to be downloaded from an external computer to the disk drive, stored in a random access memory chip on board the drive and later executed by the drive's embedded micro-controller. The serial port was typically accessed by a secondary jack or edge connector formed on a printed circuit board carrying the drive circuitry, but not conveniently available once the drive was installed within a computer cabinet or housing.
While the additional port capability is useful within the drive design, checkout and manufacturing operations, this capability is not generally available at the user/customer site. For example, the secondary connector was generally inaccessible after the drive was installed into a computer cabinet, such as a personal computer, and was accessible only after first removing the drive from the computer housing or by disturbing the computer's wiring.
Most mass storage devices present a front panel appearance within the computer housing. This is particularly true of digital tape drives, and disk drives servicing removable media. Hard disk drives are also frequently provided with a panel bezel which is presented as part of the front panel of the computer. A hard disk drive activity light-emitting diode (LED) is most frequently included in the front panel bezel, in order to provide a visual indication of hard disk drive activity during computer operations.
It is known to connect certain peripheral devices to a computer via a wireless connection. For near range connections, infra-red light transmission and reception is an available choice. One example of a battery powered computer keyboard employing one-way wireless signaling to a personal computer is described in U.S. Pat. No. 4,628,541 to Beavers, entitled: "Infra-Red Data Communications System for Coupling a Battery Powered Data Entry Device to a Microcomputer". Other examples of near range wireless paths are known. U.S. Pat. No. 5,539,658 to McCullough, entitled: "Electronic Presentation System Using Portable Storage Media" describes a wireless communications path from a laptop computer to an electronic display device, enabling remote selection of images from an image database previously copied to the display device. U.S. Pat. No. 5,402,518 to Lowery, entitled: "Sound Storage and Sound Retrieval System Having Peripheral with Hand Operable Switches", describes a wireless hand held voice recording and playback peripheral device which works in conjunction with a programmed personal computer to record and play back sound files.
A hitherto unsolved need has remained for an effective way of accessing a mass storage device via a wireless bidirectional secondary data path accessible via a front panel of the device and/or after the device has been installed in a computer without disturbing the computer cabling.